用压力探测普鲁士蓝的缺陷,水分和组成的影响
Hanna L B Boström1,2,3, Ines E Collings4, Dominik Daisenberger5
1Max Planck Institute for Solid State Research, Heisenbergstraße 1, D-70569 Stuttgart, Germany.
Journal of the American Chemical Society
|February 25, 2021
概括
普鲁士蓝色类似物 (PBA) 的缺陷提高了灵活性,降低了它们的散装模量. 水分和成分显著影响它们的压缩性和压力下的相变.
科学领域:
- 材料科学
- 固态化学
- 晶体学
背景情况:
- 普鲁士蓝色类似物 (PBA) 拥有庞大的组成空间 (AM[M'(CN) 6]·nH2O) 提供多种功能.
- 对于PBA的组成和物理特性,如灵活性和相位过渡行为之间的关系尚不清楚.
- 了解这些特性对于基础科学和工业应用都至关重要.
研究的目的:
- 调查结构特征 (缺陷,水分,组成) 如何影响PBA的压缩性和相位行为.
- 使用可变压力衍射技术探索这些因素的影响.
- 为合理设计PBA提供见解.
主要方法:
- 变压X射线衍射
- 变压中子衍射
- 结构特征分析,包括缺陷,水分和组成
主要成果:
- 缺陷显著增强PBA的灵活性,导致低散装模量 (B0 ≈6 GPa).
- 间歇性水增加了体积模量,并在有缺陷的PBA中诱导压力驱动的相位过渡.
- 固态测量 MnPt ((CN) 6 压缩性不受水化影响,但高压相位过渡会发生变化. AMnCo(CN) 6 (AI = Rb, Cs) 由于八面倾斜而表现出压力诱导的从F4̅3m到P4̅n2的转变,可通过A位子调节. Rb0.87Mn[Co(CN) 60.91显示进一步的对称性通过不适当的铁电机制降低到极空间组Pn.
结论:
- 结构缺陷,水分和组成是PBA可压缩性和相位过渡的关键因素.
- 有缺陷的PBA具有显著的灵活性,而水化在调节机械和结构反应方面起着复杂的作用.
- 通过控制它们对压力的反应,这些发现有助于合理设计PBA用于各种应用.
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